U.S. patent number 4,399,783 [Application Number 06/356,014] was granted by the patent office on 1983-08-23 for interference fit cylinder liner.
This patent grant is currently assigned to Deere & Company. Invention is credited to Herbert J. Hauser, Jr..
United States Patent |
4,399,783 |
Hauser, Jr. |
August 23, 1983 |
Interference fit cylinder liner
Abstract
An interference fit cylinder liner is disclosed for use in an
internal combustion engine. The cylinder liner comprises a long
hollow cylindrical member open at both ends and having a smooth
circular interior surface of uniform diameter. At one end of the
cylindrical member is a deflectable thin wall portion having a
circumferential convex cross-sectional outer contact surface. This
thin wall portion is deflectable inward to form a tight seal with
an inner surface of the cylinder head as the cylinder head is
mounted to the cylinder block. This tight seal prevents the leakage
of combustion gases from the combustion chamber to other parts of
the engine.
Inventors: |
Hauser, Jr.; Herbert J.
(Waterloo, IA) |
Assignee: |
Deere & Company (Moline,
IL)
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Family
ID: |
26837755 |
Appl.
No.: |
06/356,014 |
Filed: |
March 8, 1982 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
|
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139984 |
Apr 14, 1980 |
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Current U.S.
Class: |
123/193.3;
123/193.2; 123/41.84 |
Current CPC
Class: |
F16J
10/04 (20130101); F02F 1/163 (20130101); F02B
3/06 (20130101) |
Current International
Class: |
F02F
1/16 (20060101); F02F 1/02 (20060101); F16J
10/04 (20060101); F16J 10/00 (20060101); F02B
3/06 (20060101); F02B 3/00 (20060101); F02F
001/18 () |
Field of
Search: |
;123/193R,193C,193CH,41.67,41.72,41.83,41.84 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
Primary Examiner: Feinberg; Craig R.
Parent Case Text
This is a continuation of application Ser. No. 139,984, filed Apr.
14, 1980 now abandoned.
Claims
I claim:
1. In an internal combustion engine having a cylinder block with an
opening formed therein, a cylinder liner fitted throughout a
substantial portion of its entire length in said opening of said
cylinder block to form a cylindrical bore, and a cylinder head
mounted to said cylinder block to close one end of said cylindrical
bore, said cylinder head having a circular pocket with a
circumferential side surface into which extends a portion of said
cylinder liner, wherein the improvement comprises:
(a) an interference fit cylinder liner including a hollow
cylindrical member with an interior surface of substantially
uniform diameter and a contoured exterior surface, said cylindrical
member having a thin wall formed at an end thereof which has a
contact surface and contact free surfaces, said contact surface
having a circumferential convex cross-sectional profile that
extends above said cylinder block into said circular pocket of said
cylinder head, said contact surface being deflected inward upon
contact with said circumferential side surface of said circular
pocket as said cylinder head is mounted onto said cylinder block
and said contact free surfaces being spaced apart from adjacent
surfaces of said circular pocket forming a clearance which is free
of intermediate members therebetween; and
(b) sealing means for preventing combustion gases from passing
between said cylinder block and said cylinder head, said sealing
means contacting said exterior surface of said cylindrical member
adjacent to said contact surface.
2. An interference fit cylinder liner comprising a hollow
cylindrical member having an interior surface of substantially
uniform diameter and a contoured exterior surface, said cylindrical
member further having a thin circumferential wall approximate an
end thereof with a contact surface and contact free surfaces, said
contact surface having a convex cross-sectional profile which is
deflected inward upon contact with an annular surface of a recess
formed in a cylinder head and said contact free surfaces being
spaced apart from adjacent surfaces of said recess forming a
clearance which is free of intermediate members therebetween.
3. The interference fit cylinder liner of claim 2 wherein said thin
wall is resilient.
4. An interference fit cylinder liner comprising a hollow
cylindrical member having a thin circumferential wall approximate
an end thereof, said thin circumferential wall having a contact
surface and contact free surfaces, said contact surface having a
convex cross-sectional profile which is deflected inward upon
contact with an annular surface of a recess formed in a cylinder
head and said contact free surfaces being spaced apart from
adjacent surfaces of said recess forming a clearance which is free
of intermediate members therebetween.
5. The interference fit cylinder liner of claim 4 wherein said thin
circumferential wall has a smaller outside diameter than another
portion of an exterior surface of said cylindrical member.
6. The interference fit cylinder liner of claim 4 wherein said thin
circumferential wall is resilient.
7. In an internal combustion engine having a cylinder block with at
least one cylindrical bore formed therein and a cylinder head
mounted to said cylinder block to close one end of said cylindrical
bore, said cylinder head having a circular pocket formed therein
with a circumferential side surface, wherein the improvement
comprises:
an interference fit cylinder liner including a hollow cylindrical
member disposed in said cylindrical bore, said cylindrical member
having a contoured exterior surface with a thin wall formed at an
end thereof, said thin wall having a smaller outside diameter than
another portion of said exterior surface of said cylindrical member
and having a contact surface and contact free surfaces, said
contact surface having a convex cross-sectional profile that
extends above said cylinder block into said circular pocket, said
contact surface being deflected inward upon contact with said
circumferential side surface of said circular pocket as said
cylinder head is mounted onto said cylinder block and said contact
free surfaces being spaced apart from adjacent surfaces of said
circular pocket forming a clearance which is free of intermediate
members therebetween.
8. The interference fit cylinder liner of claim 7 wherein said thin
wall is resilient.
9. The interference fit cylinder liner of claim 7 wherein said
contact surface of said thin wall has a spherical cross-sectional
configuration.
10. The liner of claim 7 wherein said thin wall is self-energized
into a sealing position with said circumferential side surface of
said cylinder head by internal combustion pressures.
Description
FIELD OF THE INVENTION
This invention relates to an interference fit cylinder liner for an
internal combustion engine and more particularly to an interference
fit cylinder liner for high compression engines.
BACKGROUND OF THE INVENTION
The use of cylinder liners in engine blocks has been known for many
years. The principle purpose of such liners is to reduce the cost
of remachining the cylinder bores of an engine after a long period
of operation. In addition, such liners aid in sealing the engine
head to the engine block and therefore help in preventing
combustion gases from leaking into other parts of the engine. Two
common examples of conventional cylinder liners are taught in U.S.
Pat. No. 2,617,401, issued in 1952 to Rippingille and in U.S. Pat.
No. 2,721,542, issued in 1955 to Sheppard. With advances in
technology, the internal pressures of combustion engines has
increased, and today, it is not uncommon to find engines operating
with combustion pressures within the range of 10,000 to 20,000 kilo
Pascals.
These higher combustion pressures have proven detrimental to an
engine's sealing gaskets and have also reduced the ability of the
conventional liners to seal of leaking combustion gases. Such gas
leakage is hazardous to an engine in that it affects the operating
performance, causes starting difficulty, reduces engine compression
and adversely affects the heat transferability of the engine
coolant.
Now an interference fit cylinder liner has been invented which is
capable of preventing combustion gases from leaking to other parts
of an engine. This new cylinder liner is particularly useful in
high compression engines, such as high pressure diesel engines,
where it is even more desirable to stop combustion gas leakage.
SUMMARY OF THE INVENTION
Briefly, this invention relates to an interference fit cylinder
liner for use in an internal combustion engine. This interference
fit cylinder liner is constructed of a long hollow cylindrical
one-piece member which is open at both ends. The inner surface of
the liner is smooth and has a uniform diameter so that a piston can
reciprocate therein. At one end of the one-piece cylindrical member
is a thin wall portion which contains a circumferential convex
cross-sectional contact surface which is capable of being deflected
inward. This thin wall portion extends above the top surface of the
cylinder block and contacts the inner surface of the engine head.
As the engine head, which contains a circular pocket, is mounted to
the engine block, the thin wall portion of the cylinder liner is
deflected inward. This inward deflection, caused by the thin wall
portion contacting the inner circumferential surface of the
circular pocket, produces an interference fit between the engine
head and the thin wall portion of the cylinder liner. The
interference fit is sufficient to prevent the leakage of gases out
of the combustion chamber and into other parts of the engine, even
when high peak firing pressures are present.
The general object of this invention is to provide an interference
fit cylinder liner for an internal combustion engine. A more
specific object of this invention is to provide an interference fit
cylinder liner for high compression engines.
Another object of this invention is to provide an interference fit
cylinder liner which can prevent combustion gases from leaking into
other parts of an engine.
Still another object of this invention is to provide an
interference fit cylinder liner which will reduce the force needed
to clamp the engine head onto the engine block, especially where
high peak firing pressures are present.
Other objects and advantages of this invention will become apparent
to one skilled in the art based upon the ensuing description.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a cross-sectional view of one embodiment of an
interference fit cylinder liner positioned in an engine block with
an attached engine head.
FIG. 2 is a perspective view of an interference fit cylinder
liner.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to FIG. 1, an interference fit cylinder liner 10 is
shown positioned in a cylinder block 14 of an internal combustion
engine. The internal combustion engine can be of either the
gasoline or diesel type and normally includes the cylinder block
14, a cylinder head 16, a cylinder head gasket 18 and a piston 20.
The cylinder head 16 is mounted to the cylinder block 14 by a
plurality of mounting bolts (not shown) thereby closing off one end
of a cylinder bore 12. As shown, the cylinder head 16 contains a
circular pocket 17 having an inner circumferential surface 19 into
which a portion of the interference fit cylinder liner 10
extends.
The piston 20, which reciprocates within the cylinder bore 12, is
connected in a conventional manner by a connecting rod 22 to a
crankshaft, not shown. Surrounding the circumference of the piston
20 are a series of piston rings, two of which are depicted as 24
and 26. These piston rings, 24 and 26, are fitted to the piston 20
and slidably contact an interior surface 30 of the cylinder liner
10. The piston rings 24 and 26 serve to seal in both the combustion
gases and the compression pressures produced in a combustion
chamber 28 as well as preventing oil contained in the crankcase
from leaking into the combustion chamber 28.
The interference fit cylinder liner 10, which can be either a wet
or a dry liner, is a long hollow cylindrical member open at both
ends as better seen in FIG. 2. This interference fit cylinder liner
10 contains a smooth circular interior surface 30 of substantially
uniform diameter and a contour exterior surface 32. As used through
this application, the interference fit cylinder liner 10 will be
described as being in an upright position within the cylinder block
14. This is strictly for explanation purposes only and should not
be viewed as a limitation since the interference fit cylinder liner
10 can also be used in various types of engines having slanted or
horizontally aligned cylinder bores.
At the upper end of the interference fit cylinder liner 10 is a
thin wall portion 34 having a circumferential convex
cross-sectional contact surface 36. The shape of this contact
surface 36 can be altered to include a spherical surface or a
curved sector surface. It is preferred that a bowed or
geometrically arc-shaped configuration be used in order to obtain a
good seal. The thin wall portion 34, which is preferably resilient
within its elastic limit, can be deflected inward by mounting the
cylinder head 16 to the cylinder block 14. As the inner
circumferential surface 19 of the cylinder head 16 is forced down
over the thin wall portion 34, an interference fit is established.
This interference fit is also self-energized by the combustion
pressures within the combustion chamber 28. As the pressure
increases, due to detonation of the fuel mixture, the thin walled
portion is further forced against the cylinder head 16. This action
creates a tighter seal and is beneficial in preventing combustion
gases from leaking from the combustion chamber 28 to other parts of
the engine. In particular, the interference fit cylinder liner 10
can prevent the leakage of combustion gases in high compression
engines and in high pressure diesel engines. The leakage of such
combustion gases in an engine is detrimental in that it noticeably
affects the engine performance. Starting difficulties, reduced
engine compression and diminished heat transferability by the
engine coolant are but some of the frequently encountered
problems.
The interference fit cylinder liner 10 is tightly disposed in the
cylinder block 14 and is vertically retained in position by a
shoulder 38 which abuts a seat 40 of the cylinder block 14. The
shoulder 38 is located on the exterior surface 32 of the
interference fit cylinder liner 10. When the shoulder 38 is in
contact with the seat 40, the thin wall portion 34 will be above
the upper surface of the cylinder block 14. This position is
important because the circular pocket 17 of the cylinder head 16
must fit over the extending thin wall portion 34 and preferably
does not touch a top surface 42 of the interference fit cylinder
liner 10. If the cylinder head 16 contacted the top surface 42, it
could mushroom the interference fit cylinder liner 10, thereby
restricting the reciprocating action of the piston 20. Such action
could also cause the interference fit cylinder liner 10 to buckle
or be deformed out of round, thereby interfering with the piston 20
and the piston rings 24 and 26.
In addition to the interference fit cylinder liner 10, a sealing
means 44, such as an elastomer ring, can be positioned between the
cylinder block 14 and the cylinder head 16. This sealing means 44
should contact the exterior surface 32 of the interference fit
cylinder liner 10 just below the thin wall portion 34. This sealing
means 44 will provide a backup to prevent leakage of any combustion
gases which may seep past the contact surface 36. The sealing means
44 can be any high temperature elastic or rubber-like material.
These include prefabricated or liquid room temperature vulcanizing
gaskets such as sold by Dow Corning or General Electric.
Both the interference fit cylinder liner 10 and the cylinder head
16 can contain chamfer corners to assist in positioning the
cylinder head 16 over the cylinder liner 10. Other minor
variations, such as the use of O-ring seals 46 and 48, as shown
contacting the lower extremities of the exterior surface 32 of the
interference fit cylinder liner 10, can be utilized if desired.
EXAMPLE
For a standard size diesel engine having a peak firing pressure
between 3,500-21,000 kilo Pascals, a firing temperature between
1,500.degree.-2,500.degree. F. and a cylinder bore of approximately
130 millimeters, an interference fit cylinder liner 10 of the
following dimensions can be used. The interference fit cylinder
liner 10 can be approximately 7-10 mm in wall thickness with the
thin wall portion 34 being a millimeter or two less. The
interference fit between the cylinder head 16 and the thin wall
portion 34 can be about 0.05-0.25 mm, preferably 0.2-0.2 mm. The
length and diameter of the interference fit cylinder liner 10 will
depend upon the piston stroke and diameter. The circumferential
convex cross-sectional contact surface 36 can be about 1-2 mm wide
and should be located about 5 mm down from the top surface 42.
While the invention has been described in conjunction with a
specific embodiment, it is to be understood that many alternatives,
modifications, and variations will be apparent to those skilled in
the art in light of the aforegoing description. Accordingly, it is
intended to embrace all such alternatives, modifications, and
variations which fall within the spirit and scope of the appended
claims.
* * * * *